Jadwiga Malczewska-Lenczowska, Romuald Stupnicki and Beata Szczepańska
Prevalence of iron deficiency in male elite athletes
Study aim: To assess the prevalence of iron deficiency in competitive male athletes.
Material and methods: In total, 90 elite athletes practicing judo, rowing, pentathlon, volleyball, kayaking and biathlon, aged 16-33 years, were studied. Blood morphology indices: haemoglobin concentration (Hb), hematocrit (Hct), red blood cell count (RBC), leucocyte count (WBC), mean corpuscular haemoglobin concentration (MCHC), mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH) were determined. The concentrations of ferritin, soluble transferrin receptor (sTfR) and iron, as well as total iron binding capacity (TIBC), were determined in serum. Additionally, erythropoietin (EPO) was assayed in subjects with elevated sTfR levels.
Results: In no case iron-deficiency anaemia was found, but in 43% of subjects iron deficiency was detected. This included first stage of iron deficiency (iron depletion; ID) in 13% of subjects (ferritin <20 μg/L), and iron-deficient erythropoiesis (IDE) in 30% of subjects (ferritin <16 μg/L and sTfR> 2.75 mg/L). In all subjects with IDE, the concentrations of EPO were within normal range. The haematological indices remained unaffected in iron-depleted subjects, but in iron-deficient erythropoiesis subgroups the mean values of haemoglobin concentration and hematocrit were significantly lower than in subjects with normal iron stores (NIS).
Conclusion: Despite the lack of anaemia among studied athletes, the incidence of latent iron deficiencies (iron depletion and iron-deficient erythropoiesis) was very high. The increasing incidence of iron deficiency, together with apparent decreases of haematological indices in subjects with iron-deficient erythropoiesis, markedly augments the risk of anaemia in young, competitive male athletes. Therefore, that category of subjects should be periodically screened for iron deficiency.
Andrzej Pokrywka, Zbigniew Obmiński, Jadwiga Malczewska-Lenczowska, Zbigniew Fijatek, Ewa Turek-Lepa and Ryszard Grucza
Herbal and nutritional supplements are more and more popular in the western population. One of them is an extract of an exotic plant, named Tribulus terrestris (TT). TT is a component of several supplements that are available over-the-counter and widely recommended, generally as enhancers of human vitality. TT is touted as a testosterone booster and remedy for impaired erectile function; therefore, it is targeted at physically active men, including male athletes. Based on the scientific literature describing the results of clinical trials, this review attempted to verify information on marketing TT with particular reference to the needs of athletes. It was found that there are few reliable data on the usefulness of TT in competitive sport. In humans, a TT extract used alone without additional components does not improve androgenic status or physical performance among athletes. The results of a few studies have showed that the combination of TT with other pharmacological components increases testosterone levels, but it was not discovered which components of the mixture contributed to that effect. TT contains several organic compounds including alkaloids and steroidal glycosides, of which pharmacological action in humans is not completely explained. One anti-doping study reported an incident with a TT supplement contaminated by a banned steroid. Toxicological studies regarding TT have been carried out on animals only, however, one accidental poisoning of a man was described. The Australian Institute of Sport does not recommend athletes’ usage of TT. So far, the published data concerning TT do not provide strong evidence for either usefulness or safe usage in sport.